Sandwich structures are used in a wide variety of applications across a wise range of industries. Sandwich structures are constructed of a lightweight core bounded on opposing sides by face sheets. The face sheets may be formed of metallic material or non-metallic material. The core may have a cellular construction such as foam or honeycomb. The core may also be formed in a corrugated configuration or as a truss structure. Due to the relatively light weight of the core, sandwich structures advantageously have a relatively high stiffness-to-weight ratio as compared to solid metallic panels and solid composite laminates. In addition, sandwich structures have a relatively high strength-to-weight ratio due to the relatively low density of the core.
During the design and development of a sandwich structure, mechanical properties of the sandwich structure are used in material selection and sizing. For example, static and fatigue properties of the sandwich structure such as static shear modulus, shear strength, and shear fatigue may be used in selecting the material composition, geometry, and thickness of the core and the face sheets. Static and fatigue properties of curved sandwich structures have traditionally been characterized using data derived from the testing of flat sandwich test specimens. However, when a sandwich structure with a honeycomb core is formed into a curved shape, the static and fatigue properties of the sandwich structure can change significantly relative to the static and fatigue properties of a flat sandwich structure. In this regard, traditional design methods using flat panel test data may result in the use of inaccurate mechanical properties for a curved sandwich structure, and may result in design configurations that are un-conservative.
As can be seen, there exists a need in the art for a system and method for testing curved sandwich structures that accurately characterizes the structural properties of such curved sandwich structures. In this regard, there exists a need in the art for a system and method for testing curved sandwich structures that accounts for differences in the structural properties of a curved sandwich structure when the core, such as a honeycomb core, is formed in a curved shape.